From: Hui Min Mina Chou If multiple VCPUs of the same Guest/VM run on the same Host CPU, hfence.vvma only flushes that Host CPU’s VS-stage TLB. Other Host CPUs may retain stale VS-stage entries. When a VCPU later migrates to a different Host CPU, it can hit these stale GVA to GPA mappings, causing unexpected faults in the Guest. To fix this, kvm_riscv_gstage_vmid_sanitize() is extended to flush both G-stage and VS-stage TLBs whenever a VCPU migrates to a different Host CPU. This ensures that no stale VS-stage mappings remain after VCPU migration. Fixes: 92e450507d56 ("RISC-V: KVM: Cleanup stale TLB entries when host CPU changes") Signed-off-by: Hui Min Mina Chou Signed-off-by: Ben Zong-You Xie --- Changes in v2: - Updated Fixes commit to 92e450507d56 - Renamed function to kvm_riscv_local_tlb_sanitize arch/riscv/kvm/vmid.c | 8 +++++++- 1 file changed, 7 insertions(+), 1 deletion(-) diff --git a/arch/riscv/kvm/vmid.c b/arch/riscv/kvm/vmid.c index 3b426c800480..6323f5383d36 100644 --- a/arch/riscv/kvm/vmid.c +++ b/arch/riscv/kvm/vmid.c @@ -125,7 +125,7 @@ void kvm_riscv_gstage_vmid_update(struct kvm_vcpu *vcpu) kvm_make_request(KVM_REQ_UPDATE_HGATP, v); } -void kvm_riscv_gstage_vmid_sanitize(struct kvm_vcpu *vcpu) +void kvm_riscv_local_tlb_sanitize(struct kvm_vcpu *vcpu) { unsigned long vmid; @@ -146,4 +146,10 @@ void kvm_riscv_gstage_vmid_sanitize(struct kvm_vcpu *vcpu) vmid = READ_ONCE(vcpu->kvm->arch.vmid.vmid); kvm_riscv_local_hfence_gvma_vmid_all(vmid); + + /* + * Flush VS-stage TLBs entry after VCPU migration to avoid using + * stale entries. + */ + kvm_riscv_local_hfence_vvma_all(vmid); } -- 2.34.1